Excel (XLSX) Spreadsheet Skill

Claude Code supports comprehensive spreadsheet operations through the xlsx skill, enabling creation, editing, and analysis of Excel files (.xlsx, .xlsm, .csv, .tsv).

Trigger

• •When user needs Excel spreadsheet creation or editing
• •Financial modeling or data analysis required
• •Spreadsheet formulas and calculations needed
• •Data import from CSV/TSV files

Core Capabilities

Primary functions include:

• •Creating new spreadsheets with formulas and formatting
• •Reading and analyzing spreadsheet data
• •Modifying existing files while preserving formulas
• •Data visualization and analysis
• •Formula recalculation and validation

Key Requirements

Formula Standards:

• •ZERO formula errors (#REF!, #DIV/0!, #VALUE!, #N/A, #NAME?)
• •Use Excel formulas rather than hardcoded values
• •Dynamic and updateable through formulas

Financial Modeling Conventions:

• •Color-coding: blue (inputs), black (formulas), green (internal links), red (external links)
• •Yellow background for key assumptions
• •Standard number formatting for currency, percentages, and multiples
• •All assumptions in separate cells with formula references

Workflow:

• •Leverages pandas for data analysis
• •Uses openpyxl for formula/formatting work
• •Requires recalc.py script to calculate formula values after file creation

Use When

• •Creating financial models
• •Building data analysis spreadsheets
• •Converting data to Excel format
• •Generating reports with calculations
• •Creating templates for recurring tasks
• •Automating spreadsheet updates